Starter fertilizer is defined as the small quantity of fertilizer nutrients applied in close proximity to the seed at planting by growers of crops. In some instances, the practice entails placing the fertilizer into the seed row directly with the seed, which is often referred to as a pop-up fertilizer. Growers of crops use starter fertilizers to enhance the development of emerging seedlings by supplying essential nutrients in accessible locations near the roots. This is especially important when crops are planted into cold, wet soils, particularly when there is minimum tillage of soil.
Nowhere in the literature have scientists defined a critical ratio or noted a specific synergy between P2O5, (phosphate) Zn and Mn when these elements are applied in concert—particularly in finely divided particles. Work to date examines the three nutrients with respect to beneficial effects on plants pairwise or singly.
Phosphorus is immobile in the soil and consequently small seedling roots have difficulty obtaining the necessary amounts from the soil for rapid growth. For these reasons, additions of phosphorus fertilizer (often referred to as “starter fertilizer”) are routinely used to enhance early phosphorus uptake by crop seedlings, which in turn enhances early seedling growth or “pop-up”. This application strategy is often used even when overall phosphorus levels in a field may be adequate or high. Usually, recommendations call for 35 kg of P2O5 per hectare to accomplish this effect.
In certain situations, zinc may also be used as a component of a starter fertilizer. Like phosphorus, zinc is highly immobile in soil. In situations where soil tests indicate that zinc levels are inadequate or marginal, growers will use zinc as a component of a starter fertilizer as well.
Manganese is never commonly considered as a starter fertilizer and it is seldom used as a component of a starter fertilizer because among other reasons it is an immobile nutrient.
In no case does the literature refer to the benefits that would arise from using a combination of phosphorus/zinc/manganese as a coating on macronutrients, or as a starter fertilizer or pop-up fertilizer. Applicants have discovered a composition and method which mobilizes both zinc and manganese in the soil so that they can be used along with phosphorous in starter or pop up fertilizers. Such is accomplished by controlling the immediate environment around the composition including physical format, acidity conditions and composition.
Work at Brigham Young University in 2011 attempted to characterize the interaction between zinc and phosphorus fertilizer (but not manganese) and this work found that “when varying both P and Zn increasing Zn levels stimulated P uptake when ample P was present in the soil—but this did not occur when P was deficient. (Brandt, A, B Hopkins, V Jolley, B Webb, B greenwood and J Buck, 2012: “Phosphorus and zinc interactions and their relationships with other nutrients in maize grown in chelator buffered nutrient solution, J Plant Nutrition 35:1, 123-141).